Method and apparatus for detecting the dry weight per unit-length increment of a moving stream of tobacco by determining the ratio of total moisture to moisture per unit volume



Dec. 2. 1969 w. WOCHNOWSKI 3,482,152

METHOD AND APPARATUS FOR DETECTING THE DRY WEIGHT PER UNIT-LENGTHINCREMENT OF A MOVING STREAM OF TOBACCO BY DETERMINING THE RATIO OFTOTAL MOISTURE TO MOISTURE PER UNIT VOLUME 2 Sheets-Sheet 1 Filed June26, 1967 ELECT/Q0055 78% 7.9 v jaa TRODES a E m m 5 m 5 w m i 2 MM Am aP 2 L 75 A5 2 r PM u c z m 6 MM 2 A I C Q m 6 9 I. 9 H F. w .H F 5 M r ma w m 3 v, 2 MW Dec. 2, 1969 w. WOCHNOWSKI 3,482,152

METHOD AND APPARATUS FOR DETECTING THE DRY WEIGHT PER UNIT-LENGTH INCREMENT OF A MOVING STREAM OF TOBACCO BY DETERMINING THE RATIO OF TOTALMOISTURE TO MOISTURE PER UNIT VOLUME Filed June 26, 1967 2 Sheets-Sheet2 QNN I Ir W N mww INNTOR.

United States Patent Int. Cl. G(l1r 27/26 U.S. Cl. 324-61 19 ClaimsABSTRACT OF THE DISCLOSURE The throughput of tobacco which is fed in theform of a stream is determined by a computer which receives signals fromtwo capacitors. One of the capacitors produces signals which arerepresentative of dielectric prop erties and hence of moisture contentof unit volumes of successive unit-length increments, and the othercapacitor produces signals which are representative of dielectricproperties of succesive unit-length increments of the tobacco stream.The computer determines the throughout in accordance with the equationthat throughput equals total moisture content of an increment divided bythe moisture content of a unit volume of such increment.

BACKGROUND OF THE INVENTION The present invention relates to a methodand apparatus for determining a variable characteristic of a stream ofmoving particulate material, particularly for determining the mass orweight of successive increments or unit lengths of a stream of tobaccoparticles. Still more particularly, the invention relates to a methodand apparatus for indirect determination of a variable characteristic ofa stream of moving tobacco particles.

U.S. Patent No. 3,320,528 to Esenwein discloses a moisture determiningapparatus which is utilized to determine the moisture content of tobaccoor like fibrous materials. The apparatus of Esenwein utilizes a conveyora portion of which conveys an unvarying amount of tobacco between theelectrodes of a dielectric detector so that the detector determines thedielectric constant of tobacco which is tantamount to determination ofthe moisture content. The patented apparatus can determine the moisturecontent 'of successive increments of a tobacco stream irrespective offluctuations in the mass of such stream, i.e., the cross-sectional areaof the stream can vary from increment to increment as long as each suchincrement contains at least as much tobacco as the aforementionedunvarying amount which is caused to advance between the electrodes ofthe dielectric detector. Such mode of determining the moisture contentis very satisfactory and is helpful in further treatment of particulatematerial, particularly for drying or moistening of tobacco leaves ortobacco shreds prior to introduction into a cigarette making or othertobacco consuming machine.

In order to carry out certain treatments oftobacco, it is necessary toknow the exact mass of tobacco, i.e., the weight or mass of successiveincrements of a tobacco stream. This is desirable, for example, toinsure proper control of easing compounds which are sprayed over certaintypes of shredded tobacco to prevent the smoke from being offensive tononsmokers and/or for other reasons. Also, proper dosage of moisteningagents is facilitated if the changes in mass are known. In other words,it is contentdirectly influences the dielectric properties of to iceoften desirable to determine the weight of successive increments of unitlength in a tobacco stream in such a way that the readings or signalswill indicate the weight of tobacco alone, i.e., without the moisturewhich is present in such increments. This is particularly important forproper drying of tobacco which has been sprayed or impregnated with oneor more casing compounds. Such drying is most effective if the admissionof heat is controlled as a function of the moisture content and as afunction of the throughput of tobacco.

Presently known apparatus for determining the changes in mass or weightof a travelling tobacco stream normally utilize weighing devices in theform of endless belts. The upper stringer of the belt forms part of aconveyor which advances the tobacco stream, and the weight of tobacco onthe upper stringer is measured continuously in a manner as disclosed,for example, in German DAS No. 1,206,771. A serious drawback of suchweighing apparatus is that they are very complicated, expensive, proneto malfunction and occupy too much room. Furthermore, such apparatusmerely produce signals which indicate the total Weight of tobaccoparticles or shreds plus the weight of other substances, particularlymoisture. Still further, such apparatus are affected by dynamic forces.

SUMMARY OF THE INVENTION It is an important object of the presentinvention to provide a novel method and apparatus for rapid, convenient,accurate and fully automatic determination of a variable characteristicof a stream of tobacco or like particulate material.

Another object of the invention is to provide a method and apparatus fordetermining the changes in mass or weight of successive increments of atobacco stream and to determine such changes by simultaneousdetermination of another important characteristic of tobacco, such asthe moisture content or the total moisture which is present in succesiveunit lengths.

A further object of the invention is to provide an apparatus which candetermine minute as well as substantial changes in a variablecharacteristic of a travelling tobacco stream and whose operation is notaffected by dynamic forces.

An additional object of the invention is to provide an apparatus whichcan determine changes in variable characteristics of very shortincrements of a stream of moving tobacco or like particulate material.

A concomitant object of my invention is to provide a novel method andapparatus for determining the thoughput of tobacco which is conveyed inthe form of a stream without necessitating actual weighing of thestream.

' On feature of my invention resides in the provision of a method ofdetermining a variable characteristic of successive unit-lengthincrements of a moving stream of tobacco or like particulate materialwherein such characteristic influences the dielectric properties ofparticulate material, particularly of determining the mass or weight ofsuccessive increments. The method comprises the steps of generatingfirst electric signals which are representa tive of dielectricproperties of predetermined unit volumes of successive unit-lengthincrements of a moving stream, generating second electric signals whichare representative of dielectric properties of successive unit-lengthincrements of the stream, and utilizing such first and second signals todetermine the variable characteristic of each unit-length increment ofthe stream.

For example, the mass of a unit-length increment of tobacco can bedetermined by dividing the total moisture content of such increment bythe moisture content of a unit volume of the same increment. Since themoisture bacco, the mass can be calculated by causing a unit volume ofeach increment to pass between the electrodes of a first dielectricdetector which produces first signals, by causing each increment to passbetween the electrodes of a second dielectric detector which producessecond signals, and by feeding such signals into an analog or digitalcomputer which correlates the first and second signals and furnishes asuccession of output signals differing from each other in the same wayas the weight of successive unit-length increments.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved apparatus itself, however, both as to its construction and itsmode of operation, together with additional features and advantagesthereof, will be best understood upon perusal of the following detaileddescription of certain specific embodiments with reference to theaccompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic side elevationalview of an apparatus which embodies one form of my invention and isprovided with two measuring stations;

FIG. 2 is a top plan view of the structure shown in FIG. 1;

FIG. 3 is an enlarged transverse vertical sectional view as seen in thedirection of arrows from the line IIIIII of FIG. 2;

FIG. 4 is an enlarged sectional view as seen in the direction or arrowsfrom the line IVIV of FIG. 2;

FIG. 5 is a diagram of the electric circuit in the apparatus of FIG. 1;

FIG. 6 is an enlarged transverse vertical sectional view of a modifiedapparatus with three measuring stations;

FIG. 7 is a diagram of the electric circuit in the apparatus whichembodies the structure of FIG. 6;

FIG. 8 is a diagram which is similar to that of FIG. 5 but illustratesthe details of a computer which receives signals from the dielectricdetectors of the apparatus; and

FIG. 9 is a diagram of an electric circuit which utilizes a differentcomputer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and2, there is shown an apparatus for determining changes in the mass,weight or throughout of tobacco. The apparatus comprises a system ofconveyors including a feed having a supply conveyor in the form of anendless belt 15 which showers tobacco particles into a second ormeasuring conveyor having an elongated chute or trough 1 which isslightly inclined in the direction of tobacco travel and is agitated bya vibrator 10. The trough 1 is of substantially U- shapedcross-sectional outline and its left-hand portion 2 is constructed inthe same way as disclosed in the aforementioned Patent No. 3,320,528 toEsenwein. The central region of the bottom wall 4 in the portion 2 israised to form a substantially V-shaped measuring channel 7 which isflanked by two passages 8, 9 serving to collect tobacco which spillslaterally over the raised edges 5, 6 of the channel 7. The belt 15delivers tobacco at a rate which sufl'ices to fill the channel 7 so thatthis channel is always filled to the level of edges 5, 6. In otherwords, fluctuations in the rate at which the belt 15 delivers tobacco tothe chute 1 cannot influence the measurements which are carried out inthe channel 7 because the latter is filled at all times; the contents ofthe passages 8, 9 will vary in dependency on fluctuations in the rate oftobacco delivery but such fluctuations are not felt in the channel 7.The delivery end of the belt 15 is located at a level above theleft-hand end of the channel 7 (see FIG. 2) so that the inlet of thechannel 7 is filled beyond capacity but the vibrator 10 causes thesurplus to spill over into the passages 8, 9 before the particles whichremain in the channel 7 reach the first measuring station. The chute 1is mounted on two pairs of links ll, 12 and 13, 14 which enable it tomove back and forth and to convey tobacco through the channel 7 andpassages 8, 9 toward the righthand portion 3 which accommodates a secondmeasuring station. The portion 3 forms a second measuring channel 22which receives tobacco from the channel 7 and from the passages 8, 9.The channel 22 discharges tobacco onto the upper stringer of a thirdconveyor here shown as an endless take-off belt 61.

The chute 1 consists of sheet metal. The side walls of the channel 7 arelined with plates 16, 17 of insulating material which carry plate-likeelectrodes 18, 19 of a dielectric detector or capacitor 28. Theelectrodes 18, 19 are disposed opposite each other (see FIG. 12). Theside walls 20, 21 of the second channel 22 carry insulating plates 23,23 for the plate-like electrodes 25, 26 of a second dielectric detectoror capacitor 29. The electrostatic field between the electrodes 18, 19of the capacitor 28 extends across the partial tobacco stream whichadvances in the first measuring channel 7, and the field between theelectrodes 25, 26 of the capacitor 29 extends across the entire tobaccostream which advances in the second measuring channel 22.

The capacitors 28, 29 are connected with capacitance meters 30, 31 (FIG.5) which are connected with an analog computer 32. The results ofcomputations are indicated by two gauges or control boxes 33, 34.

The operation is as follows:

Tobacco furnished by the belt 15 has a certain moisture content. Suchtobacco is supplied at a rate which suffices to fill the channel 7beyond capacity whereby the surplus spills over into the passage 8and/or 9. Once the particles advance beyond the portion 2 of the chute1, they form an integrated stream which advances through the channel 22and is ultimately received on the upper stringer of the take-off belt61. Variations in moisture content of the partial stream passing throughthe channel 7 causes changes in capacitance of the capacitor 28. Thechanges are detected by the meter 30 which sends appropriate signals tothe computer 32. The intensity of signals produced by the meter 30 isindependent of the throughput of tobacco, i.e., such intensity dependssolely on the moisture content of successive unit lengths of the partialstream in the channel 7. The gauge 33 allows for visual observation ofsignals produced by the meter 30. The gauge 33 can be calibrated toindicate the moisture content in percentage or in units of volume orweight.

Successive increments of the entire tobacco stream change thecapacitance of the capacitor 29 during travel between the electrodes 25,26. Such changes cause the meter 31 to produce signals whose intensityvaries as a function of the total moisture content of successiveincrements of the entire stream. Thus, the intensity of signals producedby the meter 31 is a function of tobacco throughput as well as afunction of the moisture content. In other words, signals produced bythe meter 31 indicate the total moisture content of successiveincrements. The computer 32 compares the signals produced by meters 30,31 and sends an output signal to the gauge 34 which is calibrated tofurnish readings indicating the throughput or weight of successiveincrements of tobacco. Thus, the computer 32 eliminates the moisturecontent and furnishes readings which indicate solely the throughput orweight of tobacco in accordance with the known equation that throughputequals the moisture content of a unit increment (capacitor 29) dividedby the moisture content of a unit volume or mass of such increment(capacitor 28) or that the throughput equals total moisture content ofan increment times hundred and divided by moisture in percent.

It is often desirable to carry out more than two measurements. A portionof an apparatus which can carry out three measurements is shown in FIGS.6 and 7. FIG. 6

. illustrates an intermediate portion of a chute 41, namely,

FIG. 6 is disposed between the channels 7 and 22 (not shown) and itscapacity is less than that of the channel 7, i.e., the passages 43, 44of FIG. 6 together accommodate more tobacco than the passages 8, 9 ofFIG. 3. In other words, during advance from the discharge end of thechannel 7 toward the measuring station of the channel 42, some tobaccowill spill laterally into the passage 43 and/or 44. The passages 43, 44respectively receive tobacco from the passages 8 and 9.

The side walls 45, 46 of the channel 42 carry insulating plates 47, 48for plate-like electrodes 49, 50 of a dielectric detector or capacitor51. These electrodes are disposed in the same way as the electrodes of adielectric detector or capacitor 52 (FIG. 7) which corresponds to thecapacitor 28 of FIG. 5. The capacitor 53 of FIG. 7 corresponds to thecapacitor 29 of FIG. 5. The capacitors 51, 52, 53 are connected withcapacitance meters 54, 55, 56 which send signals to a computer 57provided with gauges or control boxes 58, 59, 60. The gauge 59 indicatesthe moisture content in accordance with changes in capacitance of thecapacitor 52, the gauge 58 indicates the throughput in accordance withchanges in capacitance of capacitors 52, 53, and the gauge 60 indicatesthe value of a characteristic in accordance with changes in capacitanceof all three capacitors.

FIG. 8 illustrates a computer 132 which can be utilized in the apparatusof FIGS. 1 to 5. The output signals of the computer 132 are transmittedto a system 134 of gauges 191-195. The capacitors 128, 129 andcapacitance meters 130, 131 respectively correspond to the parts 28, 29and 30, 31 shown in FIG. 5.

The computer 132 comprises five threshold circuits 170, 171, 172, 173,174 whose inputs are connected with the output of the capacitance meter130. The outputs of the threshold circuits 170-174 are connected withfour AND- gates 176-179 in the following way: The threshold circuit 170is connected directly and solely with the gate 176; the circuit 171 isconnected directly with the gate 177 and is further connected with thegate 176 through a negation circuit 181; the circuit 172 is directlyconnected with the gate 178 and is further connected with gates 176, 177through a second negation circuit 182; the circuit 173 is directlyconnected with the gate 179 and is further connected with gates 176-178through a negation circuit 183; and the circuit 174 is connected withgates 176-179 through a negation circuit 184. The outputs of AND- gates176-179 are connected with control windings of relays 186, 187, 188,189, and the output of the threshold circuit 174 is connected directlywith the control winding of a fifth relay 190. The limits beyond whichthe input signals received from the meter 130 cause the thresholdcircuits 170-174 to produce output signals rise from threshold circuitto threshold circuit.

The output of the meter 131 is connected with the working contacts ofrelays 186-190 each of which controls the index or pointer of one of thefive gauges 191- 195 in the system 134. It is clear that the relays186-190 can be replaced by transistors or other electronic componentswithout movable contacts.

The gauges 191-195 are calibrated to indicate the weight or mass oftobacco (variable characteristic) having a certain moisture content(parameter). For example, the gauge 191 can indicate changes in mass oftobacco having an average moisture content of percent; the gauge 192changes in mass of tobacco with average moisture content of 12 percent;the gauge 193 changes in mass of tobacco with average moisture contentof 14 percent; the gauge 194 changes in mass of tobacco with averagemoisture content of 16 percent; and gauge 195 changes in mass of tobaccowith average moisture content of 18 percent.

The threshold circuit 170 produces an output signal when the moisturecontent of unit volumes of the partial stream in the measuring channel 7of FIG. 3 is at least 9 percent; the threshold circuit 171 will producean output signal at a moisture content of at least 11 percent; and thethreshold circuits 172, 173, 174 will produce output signals at amoisture content of at least 13, 15 and 17 percent, respectively. Thus,there are formed five groups of ranges of moisture content and each ofthe gauges 191-195 is calibrated for an average value of each range(namely, 10, 12, 14, 16 and 18 percent). The threshold circuits -174insure that only one of the gauges 191- will indicate the result ofcomputation, namely, that gauge which is calibrated for a given range ofmoisture content in percent.

The moisture content of unit volumes of tobacco in the channel 7 isindicated directly by a gauge 133 which corresponds to the gauge 33 ofFIG. 5. This gauge 133 may be constituted by a high resistancevoltmeter.

FIG. 9 illustrates a modified computer 232. This computer includes anelectric dividing circuit 300 which receives signals from the output ofa meter 231 serving to indicate changes in capacitance of a capacitor229 which corresponds to the capacitor 29 of FIG. 5. Signals produced bythe meter 231 are divided by signals produced by the meter 230 whichmeasures changes in capacitance of the capacitor 228 corresponding tothe capacitor 28 of FIG. 5. The circuit 300 is a means for generating asignal as a function of the quotient of input signals received from themeters 230 and 231.

The dividing circuit 300 includes an operational amplifier 301 and afollower potentiometer 302 whose center is grounded and whose slidingarm or slider is connected with a servo 303. The inputs 304, 305 of theamplifier 301 and potentiometer 303 receive signals from the meters 231,230. The output signal is taken off at the output 306 and is used tochange the position of the index or pointer in a gauge 234. The signalat the output connection 306 is a quotient and indicates the mass orweight of tobacco in accordance with the aforementioned equation thatthe throughput equals total moisture content of an increment of unitlength divided by the moisture content of a unit volume of suchincrement. Otherwise stated, throughput equals total moisture contentThe signal received from the meter 231 indicates the total moisturecontent and the signal transmitted by the meter 230 indicates themoisture content of a unit volume or weight of tobacco. The gauge 234can be calibrated to furnish readings which indicate the throughput.

The signals at the output connection 306 can be used to effect automaticregulation of one or more machines or apparatus which treat tobacco onthe take-off conveyor 61 or downstream of the take-off conveyor. Forexample, such signals can be used to regulate the heating, drying,moistening or other action upon the tobacco stream.

A very important advantage of my apparatus is that it can determinechanges in weight or mass of relatively short increments of a movingstream of particulate material. The length of electrodes at themeasuring stations is much less than the length of weighing conveyorswhich are disclosed in the aforementioned German DAS No. 1,206,771.Moreover, dynamic forces cannot affect the accuracy of measurements inthe apparatus of my invention, and my apparatus immediately furnisheselectrical output signals which is desirable since the evaluation ofsignals is normally carried out by electrical or electronic means.

It is further clear that the method and apparatus of my invention can beused with equal advantage for determination of other variablecharacteristics of a travelling stream of tobacco or like particulatematerial. For example, the apparatus can be used to determine thedensity of successive increments of tobacco.

Though it is possible to install the capacitors 28-29, 51-53, 128-129 or228-229 at a single measuring station,

the arrangement shown in FIG. 2 is normally preferred because the twoelectrostatic fields do not interfere with each other. Of course, theelectric system of the apparatus comprises a synchronizer circuit toaccount for displacement of capacitors 28, 29 longitudinally of thetobacco stream. In other words, signals emitted by the capacitancemeters 30, 31 of FIG. 5 are produced by the same increments of thestream passing through the chute 1.

The capacitor 29 of FIGS. 1-5 could be replaced by a group of capacitorsinstalled in the channel 7 and passages 8, 9. However, this wouldcomplicate the apparatus and, therefore, I prefer at this time toprovide the chute 1 with the U-shaped channel 22 which receives all ofthe tobacco in successive unit-length increments of the stream andaccommodate a single pair of electrodes 25, 26.

The apparatus of FIGS. 6 and 7 is utilized if the electrostatic field isinfluenced by two or more unknown characteristics of the tobacco stream.Signals produced by at least one of the capacitors 51-53 shown in FIG. 7can be indicative of two or more variable characteristics. Such signalsare then fed to a suitable computer which furnishes readings indicativeof one or more variable characteristics or of a further characteristicwhich can he arrived at by resorting to known calculations. Analogcomputers are preferred in many instances because they are relativelysimple and inexpensive. However, if the calculations must be veryaccurate and/or if the signals are furnished in digital form, digitalcomputers will find preference over analog computers.

As stated before, output signals furnished by the computer 32, 57, 132or 232 can be used to directly or indirectly control further treatmentof tobacco on or beyond the take-off conveyor 61. For example, suchsignals can be used to regulate the temperature, moisture content oranother characteristic of foliate or shredded tobacco.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

What is claimed is:

1. A method of determining the dry weight per unitlength increment of amoving stream of tobacco or like particulate material wherein dry weightper unit-length influences the dielectric properties of said particulatematerial, comprising the steps of generating first electrical signalswhich are representative of dielectric properties of predetermined unitvolumes of measured unit-length increments of the stream; generatingsecond electrical signals which are representative of dielectricproperties of the entire volumes of said measured unit-length incrementsof the stream; and combining such first and second signals whereby theratios of said second signals to said first signals are indicative ofsaid dry weight per unitlength of said measured unit-length incrementsof the stream.

2. A method as defined in claim 1, wherein said first and secondelectrical signals respectively represent the moisture content ofpredetermined unit volumes of said measured unit-length increments inpercent and the total moisture content of successive unit-lengthincrements.

3. A method as defined in claim 2, wherein the mass of tobacco isdetermined in accordance with the equation m H/ h wherein m is the mass,H is the total moisture content of an increment of unit length, and h isthe moisture content of a unit volume of the same increment.

4. A method as defined in claim 2, wherein said first signals aregenerated prior to generation of said second signals.

5. A method as defined in claim 2, wherein said first signal generatingstep includes diverting from each unitlength increment a unit volume ofparticulate material and conveying such unit volume between theelectrode of a stationary capacitor.

6. A method as defined in claim 5, wherein said second signal generatingstep includes conveying successive unit-length increments of particulatematerial between the electrodes of a second stationary capacitor.

7. A method as defined in claim 1, further comprising the step ofvisually indicating the changes in said variable characteristic.

8. A method as defined in claim 1, further comprising the step ofvisually indicating the intenstiy of said first signals.

9. A method as defined in claim 1, wherein said last mentioned stepcomprises feeding said first and second signals to a computer.

10. Apparatus for determining the dry weight per unitlength increment ofa moving stream of tobacco or like particulate material wherein dryweight per unit-length influences the dielectric properties of saidparticulate material, comprising measuring conveyor means for advancinga stream of particulate material lengthwise; first dielectric detectormeans associated with said conveyor means for generating first electricsignals which are representative of dielectric properties ofpredetermined unit volumes of measured unit-length increments of thestream; second dielectric detector means associated with said conveyormeans for generating second electrical signals representative ofdielectric properties of the entire volumes of said measured unit-lengthincrements of the stream; and computer means arranged to receive andcorrelate said first and second signals whereby the ratios of saidsecond signals to said first signals are indicative of the dry weight ofsaid measured unit-length increments of the stream.

11. Apparatus as defined in claim 10, wherein said measuring conveyormeans comprises a portion provided with a measuring channel flanked byat least one overflow passage and accommodating said first detectormeans, and further comprising a feed for supplying into said channelparticulate material at a rate exceeding the capacity of said channel sothat the surplus spills over into said passage and the channel conveyssaid unit volumes of particulate material past said first detectormeans.

12. Apparatus as defined in claim 11, wherein said second detector meansis spaced from said first detector means, as considered in the directionof material advance In said measuring conveyor means.

13. Apparatus as defined in claim 12, wherein said measuring conveyormeans comprises a second portion provided with a second measuringchannel which conveys successive unit-length increments of the streamand wherein said second detector means is provided in said secondchannel.

14. Apparatus as defined in claim 11, wherein said measuring conveyormeans comprises a trough having a bottom Wall provided with two raisededges bounding said measuring channel and including two overflowpassages flanking said raised edges, said first detector meanscomprising two plate-like electrodes disposed in said channel oppositeeach other, said measuring trough further comprising a substantiallyU-shaped portion receiving particulate material from said measuringchannel and from said passages and said second detector means comprisingtwo plate-like electrodes provided in said U-shaped portion oppositeeach other.

15. Apparatus as defined in claim 11, wherein said measuring conveyormeans further includes a second measuring channel flanked by at leastone overflow passage and further comprising third dielectric detectormeans installed in said second channel and arranged to transmit to saidcomputer means third signals representa! tive of dielectric propertiesof successive unit-length increments of material passing through saidsecond channel.

16. Apparatus as defined in claim 10, wherein said computer meanscomprises means for generating output signals as a function of thequotient of said second and first signals.

17. Apparatus as defined in claim 10, for determining the mass of saidmeasured unit-length increments and wherein each of said detector meanscomprises a capacitor having a pair of plates installed in saidmeasuring conveyor means.

18. Apparatus as defined in claim 17, further comprising gauge meansconnected with said first detector means to furnish visual indicationsof the intensity of said first signals.

19. Apparatus as defined in claim 10, wherein said first and secondsignals are respectively representative of the moisture content ofpredetermined unit volumes of the measured unit-length increments inpercent and of the total moisture content of the measured unit-lengthincrements and wherein said computer means is arranged to produce outputsignals representative of the mass of the measured unit-lengthincrements of the stream.

References Cited EDWARD E. KUBASIEWICZ, Primary Examiner J. M. HANLEY,Assistant Examiner US. Cl. X.R. 131-136

